Department of Criminal Justice and Forensic Science, Hamline University, St Paul, Minnesota.
College of Criminology and Criminal Justice, Florida State University, Tallahassee.
JAMA Netw Open. 2021 Nov 1;4(11):e2133073. doi: 10.1001/jamanetworkopen.2021.33073.
Understanding the motivation of a mass shooter's intent to do harm can help practitioners and policy makers develop more effective intervention strategies.
To examine the prevalence of communication of intent to do harm, known as leakage, in a sample of 170 mass public shooters from 1966 to 2019; the characteristics of perpetrators who do and do not leak their plans; and whether leakage is a form of fame-seeking behavior or a cry for help among individuals who are in crisis or suicidal.
DESIGN, SETTING, AND PARTICIPANTS: This cross-sectional study included perpetrators who killed 4 or more people in a public space from 1996 to 2019 and were included in a comprehensive database of US mass shootings. That database was built from August 2017 to December 2019, and analysis took place from January to May 2021.
Leakage was identified and coded using publicly available records. Any communication to a third party of an intent to do harm prior to the shooting was coded as leakage. Logistic regression models were used to examine the risk factors associated with leakage. Models estimating leakage were examined to assess the 2 hypothesized pathways to leakage (the cry-for-help model and the fame-seeking model).
The 170 participants in this sample included 166 (97.7%) male perpetrators and 3 (2.3%) female perpetrators, with a mean (SD) age of 34 (12) years. Overall, 161 participants had known race and ethnicity: 11 (6.8%) Asian individuals, 35 (21.7%) Black individuals, 14 (8.7%) Latinx individuals, 7 (4.4%) Middle Eastern individuals, 3 (1.9%) Native American individuals, 89 (55.3%) White individuals, and 2 (1.2%) individuals with other race and ethnicity. Overall, 79 mass shooters (46.5%) leaked their plans. Of perpetrators who leaked their plans, 35 (44.3%) leaked specific plans about a mass shooting, and 44 (55.1%) leaked nonspecific plans about generalized violence. The study findings indicate that leakage was associated with receiving counseling (odds ratio, 7.0; 95% CI, 2.0-24.8) and suicidality (odds ratio, 3.7; 95% CI, 1.0-13.6), suggesting that leakage may best be characterized as a cry for help from perpetrators prior to their act.
In this study, nearly half of the perpetrators of mass shootings leaked their plans. Leakage was associated with receiving counseling and suicidality. Leakage is a critical moment for mental health intervention to prevent gun violence. Opportunities to report threats of violence need to be increased. Traditional threat assessment models focused on specific threats of violence may miss critical opportunities for intervention.
了解大规模枪击者实施伤害的动机有助于从业者和政策制定者制定更有效的干预策略。
在 1966 年至 2019 年间的 170 名大规模公共枪击者样本中，检查意图伤害的沟通（称为泄漏）的流行程度，了解泄漏计划的加害者的特征；以及泄漏是否是寻求名誉的一种形式，或者是处于危机或自杀状态的个体的呼救信号。
设计、环境和参与者：本横断面研究包括 1996 年至 2019 年间在公共场所杀害 4 人或以上的加害者，并纳入美国大规模枪击事件的综合数据库。该数据库从 2017 年 8 月到 2019 年 12 月建立，分析于 2021 年 1 月至 5 月进行。
使用公开记录识别和编码泄漏。枪击前向第三方传达的任何意图伤害的信息均被编码为泄漏。使用逻辑回归模型来检验与泄漏相关的风险因素。评估了估计泄漏的模型，以评估到泄漏的 2 种假设途径（呼救模型和寻求名誉模型）。
本样本中的 170 名参与者包括 166 名（97.7%）男性加害者和 3 名（2.3%）女性加害者，平均（SD）年龄为 34（12）岁。总体而言，161 名参与者已知种族和民族：11 名（6.8%）亚洲人，35 名（21.7%）黑人，14 名（8.7%）拉丁裔，7 名（4.4%）中东人，3 名（1.9%）美国原住民，89 名（55.3%）白人，2 名（1.2%）其他种族和民族。总体而言，79 名大规模枪击者（46.5%）泄漏了他们的计划。在泄漏计划的加害者中，35 名（44.3%）泄漏了大规模枪击的具体计划，44 名（55.1%）泄漏了关于一般性暴力的非具体计划。研究结果表明，泄漏与接受咨询（比值比，7.0；95%置信区间，2.0-24.8）和自杀意念（比值比，3.7；95%置信区间，1.0-13.6）有关，表明泄漏可能最好被描述为加害者在实施行为之前的呼救信号。
在这项研究中，近一半的大规模枪击者泄露了他们的计划。泄漏与接受咨询和自杀意念有关。泄漏是预防枪支暴力的心理健康干预的关键时刻。需要增加报告暴力威胁的机会。以具体暴力威胁为重点的传统威胁评估模型可能会错过关键的干预机会。
